Market squid (Doryteuthis opalescens), range from southeastern Alaska to Baja California, Mexico. The commercial fishery for this squid is consistently one of California's largest commercial fisheries in both volume and revenue. Market squid are harvested for human consumption and as bait in recreational fisheries.

The fishery is managed by the State as directed by the Market Squid Fishery Management Plan, which has been in effect since 2005. The fishery uses either seine or brail gear that is usually combined with attracting lights to capture aggregations of adult squid spawning in shallow water, in areas over sandy substrate. Market squid have short life spans (they have been aged to 10 months), and are extremely sensitive to variable ocean conditions. They play an important role in the food chain as a key forage species for many predatory fish, mammals, and seabirds.

CDFW's Marine Region works to maintain the sustainability of the fishery by monitoring commercial landings and collecting biological information such as weight, length, sex, maturity, and age. CDFW also collaborates with other researchers and institutions to gather information to increase our understanding of squid biology.